Screwless-type presser-foot clamp



Se t. 6, 1966 R. J. Ross SCREWLESS-TYPE PRESSER-FOOT CLAMP Filed Feb. 11. 1964 INVENTOR. I ROGER J. Ross W/ TNESS ATTORNEY United States Patent 3,270,695 SCREWLESS-TYPE PRESSER-FOOT CLAMP Roger J. Ross, Rockaway, N.J., assignor to The Singer Company, New York, N.Y., a corporation of New Jersey Filed Feb. 11, 1964, Ser. No. 343,977 4 Claims. (Cl. 112240) The present invention relates to sewing machines and in particular to means for securing the resser-foot to the presser-bar.

It is an object of the present invention to provide an improved quick release pressure-foot clamp.

It is another object of the present invention to provide an improved screwless type of presser-ifoot clamp.

Having in mind the above and other objects that will be evident from an understanding of this disclosure, the invention comprises the devices, combinations and arrangements of parts as illustrated in the presently preferred embodiment of the invention which is hereinafter set forth in such detail as to enable those skilled in the art readily to understand the function, operation, construction and advantages of it when read in conjunction with the accompanying drawings in which:

FIG. 1 is an elevational side view of a portion of a sewing machine equipped with the resser-foot clamp, and its associated elements, of this invention.

FIG. 2 is a side elevational view of the presser-foot clamp, partially in section, with the pre-s-ser-foot disassembled therefrom.

FIG. 3 is an exploded perspective view of the various elements comprising the presser-ifoot clamp.

FIG. 4 is a section taken substantially along line 4-4 of FIG. 1 and depicting the clamp in its locked position.

FIG. 5 is a view similar to FIG. 4 but showing the clamp in its unlocked posit-ion.

Referring now more in detail to the drawing, wherein similar reference numerals identify corresponding parts throughout the several views, represents a presserfoot clamp, substantially as shown.

A presser bar 12 suitably journaled in the head 14 includes a lower or sleeve-engaging portion 16. A presserfoot shank receiving slot 18 is cut vertically into the sleeve-engaging portion to a depth sufiicient to accommodate shank 20 of presser-foot 22. The shank receiving slot is rectangular in shape thereby to accommodate the resser-foot shank which is rectangular in cross-section. A clearance slot 24 is cut into the side of the sleeve engaging portion 16 intermediate the length of slot 18 but transversely thereto. Clearance slot 24 intercepts the shank receiving slot at 26 for a purpose which Will be described more fully herein below. The floor of slot 24 is beveled at point 26 to form a surfiace 27. Ledges 21 extending outwardly from the bottom of shank 20 provide a stop for shank 20 upon its insertion into the shank receiving slot 18. An indent 19, intermediate the length of shank 20, is adapted to be positioned adjacent to point 26 when ledges 2 1 are brought to bear against the underside of a locking sleeve 30, after the shank has been inserted into shank receiving slot 18. A coil spring groove 28 extending circumferentially about the outer portion of sleeve engaging portion 16 of the presserbar is cut int-o it at a point just above the closed end of the shank receiving slot 1 8.

Locking sleeve 30 includes a bore 32 and is formed to fit snugly about the sleeve engaging .portion 16 of presser-bar 12. Looking sleeve 30 is mounted for turning movement upon portion 16 of the presser bar. A pair of bores 34 and 36 are cut through the side of the locking sleeve 30 transverse to the longitudinal axis of the sleeve intermediate the sleeve ends. A locking pin 38 includes a 'bore engaging shank 40 adapted to fit Within 3,270,695 Patented Sept. 6, 1966 bores 34 and 36, and a handle shank 42 integrally connected with shank 40 and bent at an angle there-from such that the handle shank extends outward perpendicularly from the surface of the sleeve. A handle 44 is secured to shank 42 by any appropriate means.

Turning now to the assembly and operation of the presser-foot clam-p, reference to FIG. 3 shows a biasing spring 46 having a bar engaging end 48 and a sleeve engaging end 50, adapted to slide over sleeve engaging portion 1 6 when the spring is slightly expanded within groove 28. A vertical slot 52 cut into the surface of portion 16 intersects groove 28 and is adapted to receive end 4 8 of the biasing spring. With the biasing spring in position lock-ing sleeve 30, minus locking pin '38 is slipped over the sleeve engaging portion of the presser-bar. A vertical slot 54 cut into rim 55 of the locking sleeve engages end 50. At this point sleeve 30 cannot be moved further up along bar 12 because ends 48 and 50 of the biasing spring in engagement with slots 52 and 54 respectively, serve as a stop. Locking pin 38, with handle 44 attached, is now inserted through bore 34 and on into bore 36, the pin passing through clearance slot 24 which aligns with the bores in the unlocked position as illustrated in FIG. 5. However, it is noted that since vertical slot 54 is offset circumferentially from bore 34 the sleeve must be turned clockwise (as viewed in FIG. 3) against the tension of the biasing spring before bores 34 and 36 will line up with clearance slot 24, thereby to allow the assembler to insert pin 38 in the sleeve. Thus sleeve 30 is now locked against longitudinal movement relative to bar 12 by pin 38 in turn captured by clearance slot 24. Because spring 46 biases the locking sleeve in a counterclockwise direction and shank 40 of pin 38 is held in bores 34 and 36 of the sleeve the pin follows the sleeve around in the counterclockwise direction when handle 44 is released until .t is brought up against wall 56 of shank receiving slot 18.

To secure the presser-foot to the resser-foot bar the operator need merely grasp handle 44 and rotate the same clockwise against the tension of biasing spring 46 to clear slot 18 of locking pin 38 and thereafter insert shank 20, with the leading edge of sole plate 58 facing forward, into the shank receiving slot as far as it will go. When the engaging surface of ledges 21 have been brought up against the bottom of sleeve 30 indent 19 will be positioned at the intersection of slots 24 and 18. Indent 19 is cut diagonally across a corner of the shank 20 to provide a beveled surface 60 adjacent to and in the same plane as surface 27. FIG. 5 graphically depicts the interrelation of the pin, sleeve, bar, and shank at this point. With the presser-foot shank now in place, the operator need only release handle 44 to allow the bias generated by tensioned spring 56 to rotate sleeve 30 in a clockwise direction (as viewed from above the operatively connected clamp) to the position shown in FIG. 4. In this, the locking position locking pin 38 has engaged surface 60 of indent 1Q thereby pressing shank 20 against the Walls of shank receiving slots 18 and providing a rigid support for the presser-foot. In addition the shank of the presser-toot is locked against any vertical movement relative to the presser har. To release the presserfoot the operator has only to grasp handle 44 and rotate the same in a movement against the bias of spring 46 thereby moving pin 38 out of receiving slot 18 and indent 1'9 and into clearance slot 24. Shank 20, now cleared of the engaging pin is free to drop down out of the shank receiving slot.

From the toregoing description of the presser-foot clamp and its interrelated parts and operation it is readily understood that the present invention afford-s sewing machine operators with 'a quick, convenient and reliable means for clamping the presser toot to the presser-bar, and just as easily releasing the same. In addition, the uncomplicated design of the present invention readily lends itself to mass production methods allowing manufacturers to produce the clamp at a relatively low cost.

Numerous alterations of the structure herein disclosed will suggest themselves to those skilled in the art. However, it is to be understood that the present disclosure relates to a preferred embodiment of my invention which is for purposes out illustration only and not to be construed as a limitation of the invention. All such modifications which do not depart from the spirit of the invention are intended to be included within the scope of the appended claims.

Having thus set forth the nature of the invention what I claim herein is:

1. In a sewing machine having a presserbar including a sleeve engaging portion and a corresponding presserfoot, means for releasably clamping the presser-f-oot to the presser-bar comprising a sleeve mounted upon the sleeve engaging portion of said resser-bar, said sleeve engaging portion having a vertical shank engaging slot and a clearance slot extending transversely to the vertical shank engaging slot, means connecting the sleeve to the resser-bar for biasing the sleeve for turning movement upon said sleeve engaging portion, said presserfoot including an elongated shank, said elongated shank being adapted to fit into the vertical shank engaging slot, said shank having an indent therein, said sleeve having a pair of aligned locking pin receiving bores transverse to the longitudinal axis of the sleeve, and a locking pin adapted to slip into the pin receiving bores and through the clearance slot whereby said sleeve biasing means exerts a force which urges the locking pin into engagerment with said indent thereby locking the presser-rfoot to the pressenbar.

'2. In a sewing machine having a presser-bar and a presser-foot carried thereby, means for releasably clamping the presser-foot to the presser bar comprising a slotted lower porti n of said presser bar, a sleeve mounted upon said slotted lower portion, said slotted lower portion having a shank engaging rectangular slot cut vertically into the bottom thereof and a clearance slot extending transversely to the shank engaging vertical slot and intercepting the vertical slot intermediate its ends, the slotted lower portion of said presser bar also including a spring receiving slot extending around the periphery of said slotted lower portion above the vertical slot, a spring seated in said peripheral slot and having offset ends, the slotted lower portion of said presser-bar further including a spring engaging recess and said sleeve including a spring engaging slot, the two last mentioned slots adapted to receive the offset ends'of said spring thereby to bias said sleeve for turning movement upon the presser-bar, said sleeve including a pair of aligned bores extending through the sleeve wall transversely to the longitudinal axis of the sleeve, said presser-foot having a rectangular shank formed with a pair of ledges at one end and adapted to be inserted into said shank engaging rectangular slot, the ledges serving as a stop for the shank, said pre-sser-foo-t shank having an indent which aligns with said clearance slot 'when the shank is inserted into the shank engaging rectangular slot, and a locking pin adapted to fit into the aligned bores of said sleeve and through the clearance slot of said slotted lower portion of the resser-bar whereby said spring exerts a force on the sleeve which in turn urges the locking pin that it is holding into engagement with the shank indent thereby locking the presser-foot to the presser-lbar.

3. In a sewing machine having a presser-bar including a sleeve engaging portion and carrying a presser-foot having an elongated shank, means for releasably clamping the presser-foot to the resser-bar comprising a sleeve mounted upon the sleeve engaging portion of said presserbar, the lower portion of said pre-sser-bar having a vertically extending shank engaging slot and a clearance slot extending transversely to and interceptiong the shank engaging slot, means for biasing the sleeve for turning movement about the lower portion of the presser-bar, said sleeve having a pair of aligned locking pin receiving bores, a locking pin inserted into said locking pin receiving bores and through said clearance slot and said elongated shank having a locking pin engaging detent whereby said sleeve biasing means exerts a force which urges the locking pin into engagement with the shank indent thereby locking the resser-foot to the presser-bar.

'4. In a sewing machine having a presser-bar including a sleeve engaging portion and carrying a resser-foot having an elongated shank, means for releasably clamping the resser-foot to the presser-bar comprising a sleeve mounted upon the sleeve engaging portion of said presserbar, the lower portion of said presserbar having a vertically extending shank engaging slot and a clearance slot extending transverse to and intercepting the shank engaging slot, means for biasing the sleeve for turning movement about the lower portion of the presser-bar, a locking pin connected to said sleeve .and adapted to fit within said clearance slot, and said elongated shank having a locking pin engaging detent whereby said sleeve biasing means exerts a force which urges the locking pin into engagement with the shank indent thereby lock ing the presser-foot to the presser-bar.

References Cited by the Examiner UNITED STATES PATENTS 408,767 8/1889 Tim'm 112-240 X 2,878,765 3/1959 Gegauf 112240 2,985,127 5/1961 Reeber et al 112-240 FRANK I. COHEN, Primary Examiner.

P. D. LAWSON, Assistant Examiner. 

1. IN A SEWING MACHINE HAVING A PRESSER-BAR INCLUDING A SLEEVE ENGAGING PORTION AND A CORRESPONDING PRESSERFOOT, MEANS FOR RELEASABLY CLAMPING THE PRESSER-FOOT TO THE PRESSER-BAR COMPRISING A SLEEVE MOUNTED UPON THE SLEEVE ENGAGING PORTION OF SAID PRESSER-BAR, SAID SLEEVE ENGAGING PORTION HAVING A VERTICAL SHANK ENGAGING SLOT AND A CLEARANCE SLOT EXTENDING TRANSVERSELY TO THE VERTICAL SHANK ENGAGING SLOT, MEANS CONNECTING THE SLEEVE TO THE PRESSER-BAR FOR BIASING THE SLEEVE FOR TURNING MOVEMENT UPON SAID SLEEVE ENGAGING PORTION, SAID PRESSERFOOT INCLUDING AN ELONGATED SHANK, SAID ELONGATED SHANK BEING ADAPTED TO FIT INTO THE VERTICAL SHANK ENGAGING SLOT, SAID SHANK HAVING AN INDENT THEREIN, SAID SLEEVE HAVING A PAIR OF ALIGNED LOCKING PIN RECEIVING BORES TRANSVERSE TO THE LONGITUDINAL AXIS OF THE SLEEVE, AND A LOCKING PIN ADAPTED TO SLIP INTO THE PIN RECEIVING BORES AND THROUGH THE CLEARANCE SLOT WHEREBY SAID SLEEVE BIASING MEANS EXERTS A FORCE WHICH URGES THE LOCKING PIN INTO ENGAGEMENT WITH SAID INDENT THEREBY LOCKING THE PRESSER-FOOT TO THE PRESSER-BAR. 